body{
    color: black;
    margin: 0;
    padding: 0;
    background-color: white;
}
.titletext {
    color: black;
    text-align: center;
}
.box {
    width: 300px;
    height: 300px;
    border: 1px solid #ccc;
    margin: 0 auto;
    position: relative;
}

.box .sz {
    width: 90px;
    height: 90px;
    background: rgb(128, 199, 195);
    border: 2px #cec solid;
    position: absolute;
    font-size: 40px;
    line-height: 90px;
    text-align: center;
}

.box .sz.kong {
    border: 2px transparent solid;
    background: transparent
}

.btnbox {
    text-align: center;
    padding-top: 20px;
}

.btnbox .time {
    color: teal
}

.btnbox .jieguo {
    color: red
}
#btn {
    text-align: center;
    margin: 0 auto;
}